EM31 Pro review: the harmonic mount that came before the AM5
Where does it rank on our leaderboard
| Rank | Mount | Stars for Your Buck | Recorded UK price |
|---|---|---|---|
| 1 | TeSeek NanoTracker | 100 out of 100 | £52 |
| 2 | ClearSky ST25 | 94 out of 100 | £1,199 |
| 5 | JUWEI-14 | 89 out of 100 | £632 |
| 8 | ZWO AM5N | 71 out of 100 | £2,099 |
| 11 | ClearSky ST17 Mini | 56 out of 100 | £712 |
| 12 | EM31 Pro | 52 out of 100 | £1,679 |
| 14 | Sky-Watcher Star Adventurer 2i | 42 out of 100 | £249 |
| 17 | Sky-Watcher GTi Mount | 33 out of 100 | £435 |
| 18 | Celestron CG5 | 24 out of 100 | £299 |
Contents
- 01 Where does it rank on our leaderboard
- 02 Specifications and features
- 03 In the hand
- 04 What would you put on it?
- 05 How well does it guide?
- 06 What is it for? In my words
- 07 What it captured: the four from the review
- 08 Raw against finished
- 09 Watch the review
- 10 Every row of my showdown, and the readings behind each one
- 11 Should you buy it?
- 12 Questions and more about this review
In 30 seconds
Stars for Your Buck 52/100
Reviewed 10 Jul 2025 Updated 21 Sep 2026
- Rank
- #12 of 18 mounts
- Verdict
- With reservations
Written by Damon Scotting 10 min read
Buy it if
- you have the budget for a $2,000-class mount and want the ASIAIR, OnStep, an alt-azimuth mode and 20 kg with a counterweight
- you want the mount that averaged 0.73 arcsec in my seven-mount showdown, second of eight rows and on the podium in every round
Skip it if
- you are budget conscious: my recommendation is the JUWEI-14
- you want ZWO's polished app and hand controller rather than OnStep's basic one
Specifications and features
Against the harmonic mounts I have reviewed
Compare with
| EM31 Pro reviewed #12 of 18 | ZWO AM5N #8 of 18 | ClearSky ST25 #2 of 18 | MLAstro SAL-33 #4 of 18 | TeSeek 17 #6 of 18 | JUWEI-17 #7 of 18 | |
|---|---|---|---|---|---|---|
| Recorded UK price | £1,679 | £2,099 | £1,199 | £1,099 | £399 | £579 |
| Stars for Your Buck | 52/100 | 71/100 | 94/100 | 91/100 | 88/100 | 85/100 |
| Average guiding RMS | 0.73 arcsec | 0.99 and 1.10 arcsec | 0.66 arcsec | 0.7 to 0.8 arcsec | 0.85 arcsec | 0.40 to 0.61 arcsec on M 31, 1.52 to 1.57 on M 45 |
| Best target in my showdown | 0.61 arcsec, Heart | 0.66 arcsec, North America | 0.48 arcsec, North America | 0.41 arcsec, Elephant's Trunk | 0.45 arcsec, Heart | 0.40 arcsec, Andromeda (M 31) |
| Type | Harmonic (strain-wave) equatorial mount head with three modes on the maker's sheet: GEM, alt-az side and alt-az top (the VSF5 top-mode kit); OnStep control | Harmonic drive (strain-wave) head for equatorial and alt-azimuth use | Harmonic drive go-to equatorial mount, both axes | Harmonic (strain-wave) mount, equatorial or alt-azimuth | Harmonic (strain-wave) equatorial mount | Harmonic (strain-wave) equatorial mount |
| No-counterweight payload | 15 kg | 13 kg | 20 kg | 15 kg | 13.5 kg | 13 kg |
| Counterweight payload | 20 kg | 20 kg | 30 kg | 20 kg | 18 kg | 18 kg |
| Mount weight | 4.0 kg | 5.5 kg | 8.5 kg | 5.3 kg | 3.2 kg | 5.5 kg |
| Periodic error | not recorded | ±10 arcsec | not recorded | not recorded | not recorded | Approximately 25 arcsec peak-to-peak in one owner's unguided, drift-corrected RA test; not a factory limit |
| Gearing | RA and DEC: 17-type 100:1 strain-wave gear plus a synchronous belt, 300:1 overall; a brake on the RA motor (the maker's sheet) | Harmonic drive and synchronous belt, 300:1 | Harmonic reducers with timing belts, 300:1 on both axes | Low periodic error 17:100 harmonic drives on both axes | Two size-17 harmonic gearboxes, 400:1 on both axes | Two size-17 harmonic reducers, 400:1 |
| Control | OnStep; ASIAIR in every session I recorded; my computer and StellaVita | ASIAIR | OnStep over USB, Bluetooth, WiFi or ST-4; works with the ASIAIR | OnStep X | WiFi and Bluetooth app; ASIAIR | OnStep |
| Power | 12 V DC at 5 A in, 5.5 x 2.1 mm; 0.3 A tracking, 0.6 A slewing (the maker's sheet); the port panel on my unit: status light, Type-C USB, DC 12 V, a round hand-controller socket | 12 V DC, 3 A minimum (5 A recommended); DC out and USB-C on the saddle | 12 to 15 V, 2 to 5 A in; four 12 V 3 A DC outlets and four USB ports on the saddle | 12 V DC, 3 A minimum, 5 A recommended | 12 V, 2 A | 12 V DC; no power output port |
| Tripod or pier | 85 mm base, 3/8-16 fixing; optional EMTC44 tripod or EMH150 pier | Not included; ZWO's TC40 carbon fibre tripod is sold with it as a set | 3/8 inch, M6 or TC40 connection | 3/8 inch thread and three M6 holes, as the ZWO AM5 | Metal latitude base included; no tripod | GEM4 base; 125 mm diameter; 12 mm centre column |
| In the box | Mount; hand controller; Vixen/Losmandy saddle; mounting adapter; 0.5 m and 2 m USB 2.0 cables; soft bag | Head, hand controller with 2 m cable, travel case, 2 m USB-B and 1 m USB-C cables, performance sheet, quick guide, M6 Allen key; no counterweight bar | Mount, polar camera sticker, 1 m DC power cable, USB-C data cable, storage bag, manual | The mount head only; no power supply | The mount; no tripod | Head, data cable, counterweight bar, adjustment column, Allen key; no counterweight |
In the hand
Six frames of my own footage: the head, its ports, and four of the rigs it carried
The port panel on the head: the status light, the Type-C USB socket, DC 12 V in and the round hand-controller socket
The head with the Moon behind it, the Altair 60EDF and its guide scope on top
The Askar 103APO and the ASI2600MC on the head, the rig behind the four captures
The head on the turntable with my spec card from the showdown intro: 4.0 kg, 13 kg without and 20 kg with a counterweight, £1,699 before taxes and shipping
The Askar 185APO on the head with a counterweight bar and weight, Jul 2025
The C11 EdgeHD with the ASI2600MM Pro, a filter wheel and a guide scope on the head, counterweighted, Nov 2025
What would you put on it?
The EM31 Pro's 15 kg and 20 kg ratings under a rig you can change part by part, then the same rig on six other mounts
How well does it guide?
My seven-mount showdown of 28 to 29 Sep 2025: the published average and per-target figures, and every ASIAIR reading I could read off the frames
“The first of which is the jack of all trades. The EM31 Pro mount has lived up to its price tag by delivering some excellent results. Whilst reviewing this mount, I got the feeling that the company really tried their best to cater towards the astrophotography community and make a mount that works for you. And at 0.73 RMS, I think you can safely say that they have delivered on that.”
“And ironically, out of all of the mounts, the AM5N and EM31 Pro were the only ones I accurately polar aligned. This is because they're the only two mounts featured in today's video that don't have a laser pointer inbuilt.”
About this visualisation
This visualisation illustrates the guiding figures on this page: the published RMS for each target and the ASIAIR readings from my showdown. It is not the EM31 Pro’s precise recorded tracking, and the moving traces are drawn to those figures, not replayed from the mount.
What is it for? In my words
Features I used
The price
First things first, it's time to break some hearts by announcing its price. So, do its specifications back it up? Well, it's clear to see that its premium price matches its premium payload capabilities.
The alt-azimuth attachment
So, what does it offer that the AM5N and all the other mounts do not? Let's take a look at their product list that includes the prices of each of these additional accessories to the main mount. The first thing to note is that this mount is far more compatible with new features than any other mount. The key standout improvement being this alt-azimuth attachment. Now, the payload still remains as high as 20 kg when formatted in this style, but your viewing experience increases emphatically. This unique attachment allows you to explore the night sky better than any other strain-wave mount. So, even if you don't fancy any of the cool bells and whistles that this mount comes with, the bottom line is you're still going to get a mount just as good as the leading competitor.
The ASIAIR and OnStep
Now, I've been using this mount in cooperation with the ASIAIR, a mini computer that makes your stargazing experience a lot simpler. The EM31 Pro utilises OnStep software, the same as the JUWEI-14 and JUWEI-17 mounts. You can control the mount immediately from the hand controller attached. So the bottom line is this mount is not limited. Given the popularity of strain-wave mounts nowadays, it's not good enough just to make a product that's just as capable as the rest.
Support
Now, I'm actually personally a really big fan of the JUWEI mount. I'm yet to have an issue with mine, but with that being said, the biggest red flag with them is that if there is an issue, there's no official complaint or help department to resolve your issue with. Meanwhile, EMCAN claims to have developed a reputation for having an outstanding customer support system in place. And to be honest, based on the immensely thorough and detailed guides they supply, I think all the help you need is in here anyways.
Tracking
So, from my own user experience, the mount's a delight and will be sitting on top of my pier mount for the foreseeable future as a mainstay.
What it captured: the four from the review
Askar 103APO, 60 x 60 s unguided
M 81 and M 82
- Integration
- 1 h (60 x 60 s, unguided)
- Field
- 1.59 x 1.07 degrees
- Telescope
- Askar 103APO
- Camera
- ZWO ASI2600MC
- Mount
- EM31 Pro
- Target
- M 81 and M 82
- Type
- galaxy pair
- Location
- Bortle 6.8 (in my garden)
M 13
- Integration
- 1 h (60 x 60 s, unguided)
- Field
- 3.15 x 2.09 degrees
- Telescope
- Askar 103APO with the 0.6x reducer
- Camera
- ZWO ASI2600MC
- Mount
- EM31 Pro
- Target
- M 13
- Type
- globular cluster
- Location
- Bortle 6.8 (in my garden)
M 101 Pinwheel Galaxy
- Integration
- 1 h (60 x 60 s, unguided)
- Field
- 1.90 x 1.25 degrees
- Telescope
- Askar 103APO
- Camera
- ZWO ASI2600MC
- Mount
- EM31 Pro
- Target
- M 101 Pinwheel Galaxy
- Type
- galaxy
- Location
- Bortle 6.8 (in my garden)
Leo Triplet
- Integration
- 1 h (60 x 60 s, unguided)
- Field
- 1.86 x 1.25 degrees
- Telescope
- Askar 103APO
- Camera
- ZWO ASI2600MC
- Mount
- EM31 Pro
- Target
- Leo Triplet
- Type
- galaxy group
- Location
- Bortle 6.8 (in my garden)
Raw against finished
Watch the review
The 2 targets, the raw combined stack against my finished image, each with its integration, the camera and the palette:
- IC 434 Horsehead Nebula: 1 h 9 min (23 x 180 s) of light, ASI2600MM Pro, SHO narrowband, the raw combined stack with one automatic stretch
- M 27 Dumbbell Nebula: 1 h 3 min of light, ASI2600MM Pro, SHO narrowband, the raw combined stack with one automatic stretch
EM31 Pro Mount review - Better than the AM5N/Juwei? · published 10 July 2025 · 7:01 · Watch on YouTube · 10,259 views, 412 likes on 2 Oct 2026
Jump to
- 0:38 The price, and the AM5N
- 1:31 The ASIAIR, OnStep and the hand controller
- 2:56 The company behind it
- 4:20 Tracking, and the pier
- 5:30 Four captures with the Askar 103
Transcript of the review video 1,181 words · 8 chapters · searchable
Press a time stamp to play from there.
0:00 An e-mail from a company I had never heard of
0:05 The company EMCAN produce the EM31 Pro strainwave mount, a mount that on specifications and features alone slightly outranks the highly popular and recently released AM5N mount, which is undoubtedly surprising since I'd never heard of it before. 0:22 In today's video, I'm going to be testing it out as well as comparing it to its competitors in order to determine whether or not this unknown mount is in fact the best value for money mount on the market. 0:31 I'm Damon Scotting and this is Astronomical.
0:38 The price, and the AM5N
0:40 First things first, it's time to break some hearts by announcing its price. 0:40 So, it's certainly on the more premium side of things. 0:43 So, do its specifications back it up? 0:45 Well, it's clear to see that its premium price matches its premium payload capabilities. 0:49 is ever so slightly better value for money than the ZWOO AM5N mount, but I wouldn't say the savings are enough to make me want to go out and invest in this seemingly unknown mount instead. 0:59 So, what does it offer that the AM5N and all the other mounts do not?
1:01 The alt-azimuth attachment and the accessories
1:04 Let's take a look at their product list that includes the prices of each of these additional accessories to the main mount. 1:10 The first thing to note is that this mount is far more compatible with new features than any other mount. 1:15 The key standout improvement being this alt azimuth attachment. 1:18 Now, the payload still remains as high as 20 kg when formatted in this style, but your viewing experience increases emphatically. 1:24 This unique attachment allows you to explore the night sky better than any other Strain wave mount. 1:30 Now, I've been using this mount in cooperation with the ASIAIR, a mini computer that makes your stargazing experience a lot simpler.
1:31 The ASIAIR, OnStep and the hand controller
1:35 The ASIAIR is renowned for not playing ball with other companies gear, but when it comes to this mount, it works very nicely. 1:42 The EM31 Pro utilizes onstep software, the same as the JUWEI-14 and JUWEI-17 mounts. 1:48 You can control the mount immediately from the hand controller attached. 1:52 But one key pro for me is that I can control this mount simply via my computer or my ASIAIR and Stella as well. 1:58 So the bottom line is this mount is not limited. 2:00 Given the popularity of strain wave mounts nowadays, it's not good enough just to make a product that's just as capable as the rest. 2:08 The EM31 Pro is the most wellthoughtout and multi-purposeful strain wave mount available on today's market at a very competitive price. 2:16 You've seen me whack on two separate telescopes now to the EM31 Pro. 2:17 Now, that in itself is not unique. 2:20 In fact, any of the other mounts could do that as well. 2:23 But with this ball head and mount attachment, allowing you to attach an additional DSLR camera to your rig and record Milky Way time-lapses. 2:29 The EM31 Pro mount is just a bit more complex than the other mounts in the sense that it offers so many additional attachments you can buy to improve your setup accordingly to your needs. 2:38 It's multi-purposeful, which is nice. 2:40 Yes, I know that not all of you are going to want an Alt Azimuth attachment, but for some that will be an unbelievably useful tool. 2:47 So, even if you don't fancy any of the cool bells and whistles that this mount comes with, the bottom line is you're still going to get a mount just as good as the leading competitor.
2:56 The company behind it
3:00 So naturally, my first question to them was going to be, "What makes you so special? 3:04 Why should I choose you over the others?" 3:06 To which they wrote, "While AM5 benefits from the backing of a well-known astronomy company, we've taken mechanical design, material selection, ergonomics, functionality, and reliability to the next level." 3:17 Jouer, on the other hand, has attracted users primarily due to its low price. 3:21 However, many users on Cloudy Nights have mentioned issues with its build, quality, stability, and overall completeness. 3:28 Our product, however, is specifically designed for users seeking higher quality and a more comprehensive experience. 3:34 Now, I'm actually personally a really big fan of the Jouer mount. 3:36 I'm yet to have an issue of mine, but with that being said, the biggest red flag with them is that if there is an issue, there's no official complaint or health department to resolve your issue with. 3:46 Meanwhile, EMCAN claims to have developed a reputation for having an outstanding customer support system in place. 3:50 And to be honest, based on the immensely thorough and detailed guides they supply, I think all the help you need is in here anyways. 3:58 That safety net of having a company to fall back on, assuming something goes wrong with your, let's face it, very expensive piece of gear will mean a tremendous amount to large parts of the community, which is why people still choose the AM5 over the JUWEI-17. 4:11 So, I suppose when it comes down to comparing the quality of the JUWEI-17 and the AM5N versus the EM31 Pro, the EM31 Pro does come out on top.
4:20 Tracking, and the pier
4:20 As far as guiding goes, it tracks and slews just as well as my JUWEIs, which is amazingly well. 4:24 So, from my own user experience, the mounts a delight and will be sitting on top of my peer mount for the foreseeable future as a mainstay. 4:46 The bottom line from my point of view is that the EM31 Pro more than holds its own against its most popular competitors.
4:47 The bottom line
4:52 Based on my own experiences so far, I'm happy to vouch for the mount. 4:57 I think it's really good and I appreciate the fact that we astrophotographers are getting more of a selection when it comes to choosing these products. 5:05 Competition generally drives innovation. 5:06 So the more the marrier in that sense. 5:09 So in conclusion, the EM31 Pro is a welcome addition to this train wave market. 5:13 I say addition even though technically the EM31 was around before each of the AM5 and Joui mounts first burst onto the scene. 5:21 But yeah, I don't think you can do much wrong by purchasing it as opposed to the alternatives. 5:24 You get precisely what you pay for, which is a high quality strainwave mount. 5:28 I figured I'd finish things off here with some images that I captured using the mount and the 999 Askar 103 telescope.
5:30 Four captures with the Askar 103
5:33 These are stack shots of 60 * 1 minute unguided exposures. 6:15 You can check it out in even more detail by clicking the link in the description below. 6:17 And let me know in the comments down below if you've had any experiences with this mount before and what your own thoughts and feelings are in regards to it. 6:24 And also what features and improvements you would possibly like to see come from Strain Wave mounts in the future. 6:28 I'll be releasing another video fairly soon where I do more of a visual and price comparison between the JUWEI-14, JUWEI-17, AM5N, and EM31 Pro mount. 6:38 So, make sure you subscribed to see that as well. 6:39 Thanks for watching. 6:39 I'm Damon Scotting, and this was astronomical.
Check out more videos on the EM31 Pro
This £299 Telescope Mount Just Beat the £2,260 Mount
16 Oct 2025
Every row of my showdown, and the readings behind each one
| Mount | Stars for Your Buck | Andromeda | Heart | North America | Veil | Average |
|---|---|---|---|---|---|---|
| 1 ClearSky ST25 | 94/100 | 0.66″ | 0.69″ | 0.48″ | 0.80″ | 0.66″ |
| 2 EM31 Pro | 52/100 | 0.91″ | 0.61″ | 0.68″ | 0.73″ | 0.73″ |
| 3 TeSeek 17 | 88/100 | 1.19″ | 0.45″ | 0.83″ | 0.93″ | 0.85″ |
| 4 TeSeek 11 | 93/100 | 0.56″ | 1.47″ | 0.90″ | 0.76″ | 0.92″ |
| 5 JUWEI-14 | 89/100 | 1.37″ | 0.91″ | 0.88″ | 0.77″ | 0.98″ |
| 6 ZWO AM5N (second group) | 71/100 | 1.68″ | 0.85″ | 0.66″ | 0.78″ | 0.99″ |
| 7 ClearSky ST17 Mini | 56/100 | 1.17″ | 0.86″ | 0.77″ | 1.56″ | 1.09″ |
| 8 ZWO AM5N (first group) | 71/100 | 1.53″ | 1.28″ | 0.74″ | 0.86″ | 1.10″ |
EM31 Pro
0.73″ average, 2nd of 8
52/100 Stars for Your Buck
| Target | Readings | Mean | Range | RA | DEC |
|---|---|---|---|---|---|
| Andromeda | 14 | 0.87″ | 0.16″ to 1.16″ | 0.43″ | 0.76″ |
| Heart | 10 | 0.63″ | 0.50″ to 0.72″ | 0.43″ | 0.46″ |
| North America | 18 | 0.75″ | 0.45″ to 1.04″ | 0.58″ | 0.41″ |
| Veil | 12 | 0.78″ | 0.61″ to 1.08″ | 0.52″ | 0.58″ |
Should you buy it?
52/100 Stars for Your Buck
Pros
- “As far as guiding goes, it tracks and slews just as well as my JUWEIs, which is amazingly well.”
- “The EM31 Pro is the most well-thought-out and multi-purposeful strain-wave mount available on today's market at a very competitive price.”
- “As I found out when using the EM31 Pro, this is also very quiet.”
Cons
- “It is ever so slightly better value for money than the ZWO AM5N mount, but I wouldn't say the savings are enough to make me want to go out and invest in this seemingly unknown mount instead.”
- “The fact that this uses OnStep as well means that when you go on to the little remote control that you have here, things feel relatively basic.”
- “I think there's also something a little bit sus about the right ascension readings for the EM31 Pro here and how it seems to have some quite significant dips, but otherwise it's once again quietly having a good round.”
The bottom line from my point of view is that the EM31 Pro more than holds its own against its most popular competitors. Based on my own experiences so far, I'm happy to vouch for the mount.
Who the EM31 Pro is for
Imager with the budget for a $2,000 mount, weighing it against the AM5N
Buy
“If you have the budget to afford a $2,000 mount, then I would highly suggest you go for the EM31 Pro purely because it has a longer list of functionalities. It is compatible with the ASIAIR that is produced by ZWO. And overall, I find it to be a lot more of a flexible mount.”
“It can carry payloads up to 20 kg, the same as the AM5, and it is of course slightly cheaper.”
Visual observer who wants the alt-azimuth mode on a strain-wave head
Buy
“Yes, I know that not all of you are going to want an alt-azimuth attachment, but for some that will be an unbelievably useful tool.”
“It converts this strain-wave mount setup into the perfect visual observing setup. Still with the exact same payload, you don't have to worry about meridian flip. You don't have to worry about polar aligning. It just makes your user experience so much faster and easier.”
ASIAIR user who wants the mount to just work with it
Buy
“The ASIAIR is renowned for not playing ball with other companies' gear, but when it comes to this mount, it works very nicely.”
“But one key pro for me is that I can control this mount simply via my computer or my ASIAIR and StellaVita as well.”
Budget-conscious imager
Skip
“But if you are budget conscious, which I'm sure the vast majority of us are, then I would say without a doubt, get the JUWEI-14 mount.”
“So, it's certainly on the more premium side of things.”
Someone who wants a polished app and hand controller
Skip
“I think my main justification for it is that ZWO has a fully fleshed out system. It has a very useful app that you can connect to. The interface of it is incredible and I find this to be very user-friendly.”
“I just feel like given that they are a company that is supposed to be rivalling ZWO in terms of their product experience, they could have provided something that's a little bit better than what they currently have.”
Three alternatives I have reviewed
- ZWO AM5N the mount I compare it to in every video: the same 20 kg with a counterweight, the ASIAIR ecosystem, 0.99 and 1.10 arcsec in my showdown 71/100 £2,099 Read the review
- ClearSky ST25 the showdown winner at 0.66 arcsec: 20 kg without a counterweight and 30 with, from an 8.5 kg head 94/100 £1,199 Read the review
- MLAstro SAL-33 the same 15 kg and 20 kg ratings in my words, $1,099, OnStep X; not in the showdown 91/100 £1,099 Read the review
Questions and more about this review
Reviewed by
Damon Scotting
The Telescope Man Verified
BSc (Hons) Physics with Astrophysics and Cosmology, Loughborough University PGCE / QTS, University of Nottingham
About Damon About Damon Damon Scotting is The Telescope Man. He holds a BSc (Hons) in Physics with Astrophysics and Cosmology from Loughborough University and a PGCE with QTS from the University of Nottingham, and taught physics in secondary schools before becoming an astronomy creator. He is a contributing writer for BBC Sky at Night Magazine and the author of 42 Wonders of Our Night Sky, and his photograph of the galaxy M100 with the dwarf planet Ceres was Highly Commended in the Astronomy Photographer of the Year 2024 competition run by Royal Observatory Greenwich. He has appeared on the BBC's Blue Peter. More than 750,000 people follow his astronomy channels on YouTube, Instagram and TikTok, and he has reviewed more than 140 telescopes, mounts, cameras, filters and accessories hands-on for this site. More about Damon · How I test · Damon's book
I review all kinds of gear: most of it I buy, some is gifted and some is loaned, and all of it is reviewed the same way. How this site is funded
Ten questions, answered
Questions about the EM31 Pro
Reviewed 10 July 2025 ·Updated 21 September 2026
I review all kinds of gear. Most of it I buy, some is gifted and some is loaned, and all of it is reviewed the same way: no company sees or approves a review before it is published. Shop links marked Ad are affiliate links: I earn a commission when you buy through them, at no extra cost to you. How this site is funded
- How much can the EM31 Pro carry? With the accessories and a guide scope attached to the telescope, it is knocking right on the door of the AM5N or the EM31 Pro mount's payload capabilities, which are both stated to be 20 kg. The maker's sheet says 15 kg without a counterweight and 20 kg with; my own spec card in the showdown video says 13 kg without. The heaviest rigs I put on it were the Askar 185APO (13.5 kg tube, "at 18 kg" with accessories and a guide scope) and the C11 EdgeHD (12.5 kg tube) with the ASI2600MM Pro and a filter wheel, both with a counterweight. From my video review What would you put on it? ↓
- How well does the EM31 Pro guide? In my seven-mount showdown of 28 to 29 Sep 2025 it averaged 0.73 arcsec total RMS over four targets (0.91 Andromeda, 0.61 Heart, 0.68 North America, 0.73 Veil), second of eight rows and on the podium in every round; those are the ASIAIR readouts read off my screen recordings, not a guide log, because the ASIAIR Mini that ran it kept none. The four captures in my review are 60 x 60 s unguided at 700 mm. How well does it guide? ↓
- Does the EM31 Pro work with the ASIAIR? Every session I recorded on it ran from an ASIAIR; the ASIAIR writes the mount as OnStep in the headers, the firmware it shares with the JUWEI-14 and JUWEI-17. The specifications and the comparison table ↓
- What does the alt-azimuth attachment do? The maker sells it as the VSF5 top-mode kit ($329 on the product list in my video). I showed the maker's render and a daylight clip of the bracket; nothing is recorded from a night in the alt-az mode. The specifications and the comparison table ↓
- What are the EM31 Pro's weak points? The only real con I can think of when talking about the EM31 is that it's using the same interface as the JUWEI mount, which is OnStep. And it is not cheap: on my own card it was £1,699 before taxes and shipping, against the JUWEI-14 at £649. From my video review The specifications and the comparison table ↓
- Which rigs have you put on the EM31 Pro? The Askar 103APO with the ASI2600MC, unguided, for the four captures in my review (spring 2025); a twin-telescope rig of two catadioptric tubes on a dual bar; the Altair 60EDF with a guide scope and camera; the Askar 185APO with a counterweight (Jul 2025); the C11 EdgeHD with a 0.7x reducer, the ASI2600MM Pro, a filter wheel and a guide scope, counterweighted, for the Horsehead night (Nov 2025); and the showdown guide train of a 50 mm guide scope and an ASI120 mono (Sep 2025). What would you put on it? ↓
- How much does the EM31 Pro cost and where can I buy it? $2,129 ex-tax on the EMCAN product list in my review (Jul 2025), £1,699 before taxes and shipping on my showdown card (Oct 2025), £2,048 including VAT on my own screenshot of the AliExpress listing (8 Oct 2025). The AliExpress tab is my affiliate link; Dark Clear Skies and EMCAN's own store pay me nothing. Dated record, not a live price The verdict, the readers and the sellers ↓
- EM31 Pro or ZWO AM5N? Did I really just say only cost? The EM31 Pro is slightly cheaper than the AM5N, which is enough of a selling point, but that is not all that it's got going for it. But if you do decide to go ahead and buy the AM5N mount, you're not doing anything wrong. It is still an incredible mount. Both are rated 20 kg with a counterweight; the AM5N cost $2,299 to the EM31 Pro's $2,129 in Jul 2025 and £2,260 to £1,699 on my cards in Oct 2025. In my showdown the EM31 Pro averaged 0.73 arcsec to the AM5N's 0.99 and 1.10. From my video review The specifications and the comparison table ↓
- How many nights did you test the EM31 Pro? Not recorded. The mount was on camera by 6 May 2025 and the review was uploaded on 11 June 2025; it then carried the Askar 185 in July, ran the showdown night in September and the C11 EdgeHD night in November 2025, and it is still on my pier. No night count exists in my files.
- Is the EM31 Pro worth it? But yeah, I don't think you can do much wrong by purchasing it as opposed to the alternatives. You get precisely what you pay for, which is a high quality strain-wave mount. My score is 52 of 100, rank 12 of the 18 mounts on my board. From my video review The verdict, the readers and the sellers ↓